Composite fabric



Dec. 14, 1937. w w ROWE 2,101,874

COMPOSITE FABRIC Filed March 8, 1934 INVENTOR,

ATTORN E Y5 Patented Dec. 14, 1937 UNITED STATES COMPOSITE FABRIC William Wallace Rowe, Cincinnati, Ohio, assignor to The Paper Service Company, Lockland, Ohio, a corporation of Ohio Application March 8, 1934, Serial No. 7145 12 Claims.

My invention relates to specialized composite v fabrics. -These fabrics, as will be readily understood, are available for many uses, and in the formation of many different types of articles. In the ensuing specifications I shall describe them with particular reference to the manufacture of bags, wherein arise a number of the problems in the solution of which my invention has an especial application. It will be understood, however, that this particular use is exemplary only, and is not limiting in any degree.

The fundamental object of my invention is the provision of a composite fabric of proofed character, and in particular of waterproofed character, with certain other attendant advantages which will hereinafter be clear.

This and the other objects of my invention which will be set forth hereinafter, or will be apparent to one skilled in the art upon reading these specifications, I accomplish in those structures of.

which I shall hereinafter set forth certain exemplary embodiments. A drawing forms part of these specifications, wherein I have shown in somewhat magnified and exaggerated form, a cross-section of an exemplary fabric embodying my invention.

Hitherto bags for heavy duty, as well as a number of other articles, have been made from a composite fabric in which creped paper is cemented to a textile material such, for example, as burlap or cotton. While other adhesives have been used, the one most commonly employed is asphalt.

There is a growing use for bags and other con- 1 tainers for the shipment either of hydroscopic materials or materials which will be damaged by moisture, air or other .gases. Likewise there is a growing use for composite materials of this character in other articles or constructions wherein either the retention or the exclusion of water, moisture, gases, and the like, is essential. There has been considerable development in the formation of seam or joint structures which are in themselves more, highly resistant to penetration than seam or joint structures which have been in current use in the art; but no proofed seam or joint will be effective in producing, for example, a waterproof article, unless the. fabric itself, of which such article is made, is proofed against water or other deleterious influence.

Consequently, there is great need i'n'the industry for the development of truly proofed fabrics.

It must be remembered that in constructions of this character, the fabric is liable to strains which tend to distort it in. various directions. Thus, in a bag subject to ordinary handling, the

textile material'is bent and bulged, as well as stretched along the' diagonal. Likewise, the creped paper layer is distorted, and the asphaltic laynbetween them is subject to disrupting strains. Even assuming, therefore, that the as- 5 phaltic layer were absolutely continuous, and did render the fabric waterproof as initially formed, these disrupting strains speedily operate to destroy the proofed character of the fabric. Thus, in a bag of ordinary construction, proofing tests applied after the baghas been in use, always show a very marked and very considerable loss of resistance as compared to tests before use. Several factors are of importance here. Normally the asphalt employed must be of a fairly hard type. In bags of the character referred to, the paper isdisposed inwardly, with the cloth lying on the outside of the container. The use of soft asphalt would be productive of a staining of the burlap or other textile fabric; and under condi- 2o tions of heat, as in warm climates, or when bags are filled with hot materials, the asphalt would strike entirely through the cloth and serve to stick adjacent containers together, as well as to render the containers very unsightly. This is true as well of thick layers of the normally used and relatively hard asphaltic substances, as of layers of softer substance. l

So far as proofness is concerned, the advantage, however, lies with layers of softer asphalt, bitumen or other adhesive, because even thick layers of hard adhesive can quite readily be cracked and disrupted by the strains aforesaid, whereas softer layers, retaining a more or less continuous plasticity, not only give under such strains with- .35 out disrupting, but if disrupted, can seal themselvesin a new formation without altering the proofed character of the fabric. Softer bitumens, however, have the additional disadvantage of staining through the paper on the inside of the bag or container, so that the containers are rendered unsightly, and are not acceptable to the general public, for example, as containers for food stuffs or the like.

In the practice of my invention, I provide a construction wherein a paper layer is cemented to a layer of textile fabric with a relatively thin layer of adhesive and/or-a non-staining character of adhesive. I- provide a second paper layer displaced from the first, and I confine therebetween a layer of proofing substance, preferably of relatively soft character, and preferably also having a continuous resident plasticity as aforesaid. Since this layer is confined between layers of paper, it is prevented from coming through the textile layer.

Additionally,'either layer of paper may be treated in such a way as to prevent the softer layer of adhesive, if it has staining characteristics, from staining through said layer.

I shall now describe in detail, an exemplary em bodiment of my invention and certain modifications thereof; and for clearness, reference is now made to the drawing, wherein A represents aor of an adhesive which would tend to become soft under the influence of any condition to which the fabric might be subjected in use, and to come through the. textile layer, the layer C should be relatively thin. Aside from its moisture-proofing value, its function is, of course, to adhere together the textile layer and the other layers of my composite fabric, and this function may be of importance only until the final article has been constructed therefrom, or may be of importance.

in maintaining a continuously adhered condition throughout the life of the article. In the manufacture of bags, for example, where the inner layers, comprising paper and adhesives, have the qualities of universal stretchability, it is not necessary to maintain adhesion between the textile and the other layers throughout the life of the article.

While I prefer to make my layer of creped paper B, in accordance with the teachings of my Reissue Patent No. 17,633, i. e. by creping the paper by means of the positive adhesive action of a thermoplastic substance, such as asphalt, and while I also prefer to give the paper the qualities of universal stretchability, in accordance with the teachingsof the-co-pending application of Wil- Iiam C. Kemp, Serial No. 626,059, filed July 29, 1932, i. e. by creping the paper twice upon the diagonal, the different sets of creping crinkles crossing each other, yet such products and methods are not a limitation upon my present invention. Where the paper is creped by means of a thermoplastic, I may, for example, but again without limitation, use a high melting point asphalt, say of approximately 180 F., as obtained by the A. S. T. M. standard test. I may also use the asphalt so applied to cement the paper to the burlap or the like A, the asphalt in this case constituting the layer marked C. This, again, is not a limitation upon my invention; but I may take the same paper webs or other webs otherwise produced, and cement them to the layer A by any procedure desired.

,I have shown another layer of paper D displaced from the first layer, and having therebetween an adhesive substance or substances indicated generally at E. Preferably a part, at least, of such layer or layers comprises a proofing sub stance. Where asphalt or other bitumen is employed, this proofing layer preferably will have a relatively permanent plasticity at normal temperatures, and may be of an asphaltic substance of lower melting point, say around -l15" F., as determined by the standard test referred to above. The layer may, howeven-be of other proof ingsubstances, as set forth above.

Particularly where asphalt or other bitumen is used of fairly low melting point, it may be advisable to coat at least the upper layer of paper D where it comes thereagainst, with a substance which will prevent the staining of the ply D, by absorption of the lighter constituents of the softer coating. This proofing coat may be of any substance desired, including, but without limitation, a rubber latex; but I have found that it is sufficient tov provide the sheet D with a coating of harder asphalt similar to the harder coating described above. Therefore, in my drawing I have subdivided the layer E into a layer F of soft asphalt, and a layer G of harder asphalt comparable to the layer C. Where the paper web D is creped by means of an asphaltic substance, the layer G may comprise or consist wholly of the adhesive used in the creping step.

It will be noted that the softer layer F is, in my construction, sealedbetween layers D and B. It may tendto be absorbed, in more or less degree, by the layer B; but this is of no consequence, so faras" appearance is concerned, the layer B being an interior ply, and even is of assistance in the proofing, in that it becomes less likely for moisture to pass through a defect in the layer C, and then travel in the paper layer B until it can find another defect through, which it can pass into the interior of the bag or container made of my composite fabric. Inorder to prevent staining, where desired, it is also possible to employ paper layers having at leastone surface formed of hard sized'fibers or the like.

The manner of combining the various layers which go to make up my composite fabric, is not a limitation upon my invention. So long as a good bond 'is obtained, the paper layers may be assembled together and afterwards joined to the textile or other material, or one layer can first be joined to the textile and the other layer added with the interposition of the intervening coat or coats. It is likewise possible to use two medium melting point layers as layers G and F, but this is ordinarily not to be preferred, excepting that a double coating, where the coatings are relatively thin, has been found in practice to give a much more waterand moisture-proof article than a single coating would give. This is because a single coating may have a tendency either to be imperfect, or to be cracked or broken, whereas, when two or more coatings are used between the layers of paper, the second and/or additional coats serve to seal imperfections in the first. The

purpose of using a low melting point sealing and resilient, and does not become hard and brittle under the influence of temperature. changes or other influences to which .the fabric may be subjected. There is also a tendency in plastic layers, such as low melting point asphalts, to amalgamate somewhat with higher melting point layers, and to seal cracks therein as and when they are formed.

It will be understood that my invention is not limited to the specific embodiment which I have chosen, and not only that modifications may be made therein without departing from the spirit of my invention, but that additions may be made to such composite fabric also without such departure. There may be more thantwo paper layers, and/or the textile layer A may be faced on its arc ers outerside with paper or other material as may be desired, by way of example. I have illustrated. in my drawing, in a diagrammatic way, the general features of my invention, and what I claim as new and desire to secure by Letters Patent, is:-

l. A composite fabric comprising in the order named, a layer of cloth, a layer of adhesive, a layer of creped paper, a plurality of layers of adhesive, and a layer of creped paper.

2. The product as claimed in claim 1, in which the paper layers have the characteristic of universal stretchability.

3. A composite fabric comprising in the order named, a layer of cloth, a layer of high melting point asphalt, a layer of paper, at least one layer of low melting point asphalt, a layer of high melting point asphalt, and a layer of paper.

4. A composite fabric comprising in the order named, a layer of paper, a sealing substance, a non-brittle proofing substance, and a layer of paper, the said composite fabric being joined, as such, to a layer of cloth.

5. A composite fabric comprising a layer of cloth, a layer of paper creped by means of a thermoplastic adhesive and joined by said adhesive to said cloth, a layer of non-brittle proofing substance overlying said paper layer, and a second layer of paper creped by means of a thermoplastic adhesive, so disposed on said proofing layer that the resident film of said thermoplastic adhesive on said last mentioned paper layer lies against said proofing layer.

6. A composite fabric comprising at least two layers of paper and a plurality of layers of-cementitious substances located therebetween, one of said layers of cementitious substance being bitumen, and at least one other layer of cementitious substance being rubber derived from latex, said last mentioned layer lying adjacent one of said paper layers.

7. A composite fabric comprising at least two layers of paper and a plurality of layers of cemen-,

titious substances located therebetweem'one of said layers of cementitious substance being a layer of rubber derived from latex, and atleast one other of said layers of cementitious substancebeing a layer of bituminous material, said layer of bituminous material lying between a paper face of said composite fabric and said layer of rubber derived from latex.

8. A composite fabric comprising two layers of paper and a plurality of layers of cementitious substances located therebetween, one of. said layers, at least, being a layer of a staining adhesive, and one other of said layers, at least, being a layer of non-staining adhesive located between said layer of staining adhesive and one of said paper faces, said last mentioned paper face, at least, consisting of a layer of paper which is stretchable in all directions.

9. A composite fabric comprising cloth, a plurality of layers of paper lying on the same side of said cloth, one of which is in adhesive union therewith, a layer of staining adhesive between at least an adjacent pair of said paper layers, and a coating of stain preventing substance associated with at least the outer one of said paper layers. j

10. A composite fabric comprising a plurality of contiguous paper layers and a layer of cloth, one of said paper layers being joined to said cloth by a layer of bituminous adhesivaand a layer of bituminous adhesive disposed between said paper layers, the first mentioned bituminous layer being brittle at a temperatureof use at which temperature the second mentioned of said bituminous layers is non-brittle.

11. The product as claimed in claim 3 in which the layer of low melting point asphalt is at least partially absorbed into the intermediate layer of p p 12. A composite fabric comprising two layers of paper and a plurality of layers of cementitious substance located therebetween, one of vsaid layers at least being a layer of low melting point asphalt and another of said layers at least being a'layer of high melting point asphalt located between said layer of low melting point asphalt and one of said paper faces, said last mentioned paper I face at least-consisting of a layer of paper which is stretchable in all directions;

WILLIAM ROWE. 

